The present invention relates to rolled flexible sheet material dispensers. It particularly relates to dispensers for dispensing today's soft paper toweling wherein the towelling is dispensed by the intending user grasping and directly pulling on the paper web.
Many designs for dispensers for rolled flexible sheet material, such as paper toweling and the like, are known. Examples of dispensers are shown in U.S. Pat. Nos. 3,575,328, Re. 28,911 ('911), 3,851,810, 4,142,431, 4,206,858, 4,404,880, 4,712,461 ('461) and 4,732,306 ('306), and in copending applications Ser. Nos. 07/175,255 ('255) and 07/427,336 ('336). The contents of each of these patents and applications and any other patents, applications or publications mentioned anywhere in this disclosure are hereby incorporated by reference in their enntireties.
Such dispensers are often located in public restrooms, and thus the intending users thereof with their wet hands do not want to touch any levers or buttons to actuate the dispenser. One dispenser design which addresses this problem is actuated by the user touching only the leading edge of the toweling, grabbing and pulling down on. For example, the '461 dispenser is especially adapted for creped paper toweling where the cutting mechanism is actuated solely by the user pulling on the paper web with his wet hands. A straight sliding knife inside of the feed roller is mounted so that the knife blade follows a path parallel to and offset from the radius of the feed roller. A camming mechanism imparts a reciprocating movement to the blade, as the feed roller is rotated, by drawing on the web of material exposed at the exit of the dispenser. After the blade has cut the web of material and the feed roller rotated further through its cycle, the edge of the blade is retracted into the feed roller. Small uncut portions of the web are spaced across the width of the web, and with only a minor small increase of pulling force supplied by the user, the separated uncut portions are torn and the user thereby effectively obtains the appropriate length of toweling. At the same time, a free length of web material is provided available and disposed beneath the dispenser exit ready for and accessible to the next user. Thus, by automatically exposing a lead length of towel web, the next intending user need not touch any part of the dispenser. In other words, a preselected length of the supply web is severed by the knife as the web is being withdrawn by the user, and a lead portion of the next sheet is automatically fed outside of the dispenser convenient to the next user.
A preferred toweling is today's soft toweling having better hand-feel and better absorption characteristics than towels in the past. These new towels are typically bleached white products and examples thereof are the ULTIMA soft towel available from Georgia-Pacific Corporation of Atlanta, Ga. and the SEQUEL towel available from Scott Paper Company of Philadelphia, Pa. Such toweling, however, is by its nature weak in the machine direction. This weak toweling, when pulled with the user's wet hands, tends to tear off or "tab" in the user's hands, which can be annoying to the user and wastes toweling.
A further example of a "towel grab and pull" type of dispenser is that shown in the '336 application as well as that of the ULTIMATIC dispenser which has been available from Georgia-Pacific for a one year or so. The latter is shown, for example, in a ULTIMATIC dispenser brochure entitled "The Ultimatic Towel Dispenser System and Ultima Towel." Drawing No. P-1201-144, dated August 1989, of Georgia-Pacific and entitled "ULTIMATIC Model P12", which brochure became publicly available a little more than a year ago, and shows dispenser components. With the ULTIMATIC dispenser having a close-coupled feedout spring, a pull of forty-four ounces during the end of the cut is required for a single-ply towel and a pull of over five pounds is needed for a double-ply paper.
To prevent the large towel roll within the dispenser, when the towel free end is pulled down hard, from overspinning and then getting caught in the rolls or cutting mechanism, towel roll brakes have been provided. One form of brake, as found on the ULTIMATIC dispenser for example, comprises an inwardly disposed, tapered trinagular rib on at least one towel support arm. The arm is spring loaded to keep pressure on the towel roll and to bias it against the opposite arm. The rib is larger at its outside base than at its point or tip at the center of the arm. When the roll is large in diameter, it has a greater mass and therefore requires a greater braking force. As it decreases in diameter, it becomes lighter and has less mass and thus does not need as much braking force. Other types of known dispenser towel roll brakes are a wire-hanging type of brake wherein the towel roll sits in a wire hanger that pivots and the towel roll rests against the back plate. An example of such a brake is found in the CORMATIC dispensers available from Georgia Pacific or those described in U.S. Pat. Nos. 3,500,667 and 3,575,328. Another form includes an auxiliary, small idler roller that is spring loaded and rests on the towel roll to provide the braking force, such as is provided in various dispensers.